Givens/Jacobi plane rotations

Collaboration diagram for Givens/Jacobi plane rotations:

Topics
	lartg: generate plane rotation, more accurate than BLAS rot
	lartgp: generate plane rotation, more accurate than BLAS rot
	lasr: apply series of plane rotations
	largv: generate vector of plane rotations
	lartv: apply vector of plane rotations to vectors
	lar2v: apply vector of plane rotations to 2x2 matrices
	lacrt: apply plane rotation (unused?)

Detailed Description